DH 103 - Quiz #2

What is a stepwedge?

A device that can be used to demonstrate short-scale contrast and long-scale contrast.

What is a stepwedge composed of?

Aluminum

High contrast of a dental image

Exhibits very dark areas and very light areas

Magnification

The geometric characteristic that refers to an image that appears larger than it's actual size

The paralleling technique can result in magnification due to IR placement. What can the radiographer change to compensate for this magnification?

Use a longer PID

Radiopaque

Refers to portion of dental image that appears light or white

What dental materials appear the most radiopaque?

Metals

Radiolucent

Refers to portion of dental image that is dark or black

What part of the tooth appears the most radiolucent?

Dense materials

- Pulp, decay, cysts, etc.

An increase in density can result when there is an increase in....

mA, time, and kVp

Density

The overall darkness or blackness of an image

When there is an increase in the subject thickness, what is the result of the image?

The image has less density

Contrast

The difference in the degrees of blackness between adjacent areas on a dental image.

Which exposure factor control contrast on an image?

kVp

Distortion

A variation in the true size and shape of the object

Sharpness

The capability of the receptor to reproduce the distinct outlines of an object

What factors can improve the sharpness of an image?

Small focal spot, no movement, small crystal size (more pixels)

How can a radiographer minimize dimensional distortion?

By placing the PID perpendicular to the tooth and receptor, and receptor parallel to the tooth

If you are treating a patient that has no clinical signs of disease, how frequently should you take a FMX on this patient?

3-5 years

What is an example of an extraoral technique for a dental image examination?

Panoramic image

How many dental images would you take if you wanted to obtain a full mouth series of x-rays?

14-20

- 18 images in our clinic

What kind of image evaluates the crown, roots, and supporting bone of a tooth?

Periapical

What kind of image evaluates the interproximal areas of the crowns of both maxillary and mandibular teeth in a single image?

Bitewing

What word is used for closing or biting down?

Occlude

What kind of exam can a dental hygienist do to evaluate the maxillary or mandibular arch in one intraoral image?

Occlusal examination

What technique is used for periapical images?

The paralleling or bisecting technique

What is the purpose of the identification dot located on a traditional film?

Film orientation

What receptor size is recommended for an adult bitewing?

Size 2

When should adult bitewings be taken vertically?

Periodontal patients

What is recommended for patients that have a sensitive gag reflex?

It is recommended to take anterior images first and then complete the posterior periapicals and bite wings.

What causes overlapped IP contacts?

Always due to improper horizontal angulation

What causes foreshortening or elongation?

Always due to improper vertical angulation

Where is the mesial edge of the image receptor placed when taking a molar bitewing?

At the midline of the 2nd mandibular molar

What landmarks should be included in a molar bitewing image?

Distal of 2nd mandibular premolar

Where should the mesial edge of the image receptor be placed when taking a premolar bitewing image?

At the midline of the mandibular canine

What landmarks should be included on a premolar bitewing image?

Distal of mandibular canine

What size receptor should you used for a pedodontics patient?

Size 0

What can be used to help stabilize the receptor if a patient has an edentulous area?

Cotton roll

Penumbra

Some lack of image sharpness present in every radiograph

Periapical examination

Examines the entire tooth (crown and root) and supporting bone.

Interproximal examination

Examines the crowns of both maxillary and mandibular teeth on a single image.

Short-scale contrast (high contrast)

Black/white, low kVp

Long-scale contrast (low contrast)

Many shades of gray, high kVp

Film contrast

Qualities of the film and film processing

Subject contrast

Characteristics of the subject that influence radiographic contrast

What size receptor is used for an occlusal exam?

Size 2

Dentulous areas

Areas that exhibit teeth

Edentulous areas

Areas where teeth are no longer present

What does an increase in target-receptor distance result in? (Source of x-rays)

Less image magnification

What does an increase in object-receptor distance result in? (Tooth)

More image magnification